Russia has announced that it will suspend a communications channel with the United States - which had been set up to avoid midair incidents between Russian and US planes over Syria.
The move comes after the US conducted air strikes on a Syrian airfield, in response to the alleged chemical airstrike carried out by the Syrian regime in Khan Sheikhoun, according to The Hill.
Russia has claimed the US decision to launch airstrikes was an "act of aggression" and has condemned the bombing.
In a statement about the suspension, the Russian Foreign Ministry said: “Russia suspends the Memorandum of Understanding on Prevention of Flight Safety Incidents in the course of operations in Syria signed with the US."
The communications channel had been set up in 2015, when Russia started to intervene in Syria.
Before this line was established US and Russian aircraft had a few near-misses in the sky.